The present invention relates to a vehicle electrical system with dual generator/battery sets.
Typical vehicle starting and charging systems usually include a single alternator or generator, a single starter motor, a single battery composed of many cells in series and/or in parallel and a multiplicity of loads. Such systems are usually protected by fusing the individual loads. With such a system, a failure of the generator or alternator will result in depletion of the battery and the interruption of power to all the loads.
A dual alternator, dual battery emergency vehicle electrical system is described in U.S. Pat. No. 4,347,473 issued Aug. 31, 1982 to Stroud. In the Stroud system, there are two electrical load groups--an emergency load group and a "vehicle chassis" load group. The vehicle chassis load group includes loads such as the vehicle lights, radio, heating and cooling system, starting circuit and ignition circuit. Thus, with the Stroud system, under normal circumstances, energy from only one battery will be available to the starting circuit.
Also in the Stroud system, there is no group of electrical loads which is permanently connected to both batteries. Furthermore, a short circuit fault in either load will draw current from both alternators.